1. Field of the Invention
The present invention relates to a manufacturing method of an electric motor.
2. Description of Related Art
In a previously proposed manufacturing method of an electric motor, a coil connecting process is executed to electrically connect a plurality of coils to a commutator, which includes a plurality of commutator segments that are arranged one after another in a circumferential direction along an outer peripheral surface of a generally cylindrical dielectric body. A slidably contacting portion is formed in one axial side of each commuter segment to slidably contact brushes. Furthermore, a claw portion (a commutator riser), to which the corresponding coil is engaged, is formed in the other axial side of the commutator segment. In the coil connecting process, the claw portion, to which the corresponding coil is engaged, is radially inwardly pressed by a fusing electrode to weld (fuse) the claw portion to the corresponding coil (see, for example, Japanese Unexamined Patent Publication Number 2004-147495 corresponding to U.S. Pat. No. 7,084,546 B2).
However, in the above coil connecting process, at the time of radially inwardly pressing and welding the claw portion, the slidably contacting portion side (one axial side) of the commutator segment, which is opposite from the other side (claw portion side) of the commutator that is pressed by the fusing electrode, may possibly be radially outwardly lifted from the dielectric body. This may cause formation of a step in the outer peripheral surface of the commutator (the slidably contacting portion). The formation of the step may result in occurrence of improper commutation, generation of vibration and/or generation of noise.